INCREASED BRAIN NAD PREVENTS NEURONAL APOPTOSIS IN-VIVO

Apoptosis is a characteristic form of cell death which has been implic ated in neurodegeneration. In this study we document the induction of apoptosis and DNA fragmentation in vivo by 1-methyl-4-phenyl-1,2,3,6-t etrahydropyridine (MPTP), a neurotoxin. MPTP selectively damages dopam inergic neurons in the substantia nigra of the midbrain. It is a poten t inducer of oxygen radicals. Nicotinamide, a precursor of NAD, is abl e to block the apoptosis induced by MPTP. Nicotinamide also quenches s ome of the radicals formed by xanthine oxidase. Nicotinamide may be of interest in the treatment of neurodegeneration. (C) 1997 Elsevier Sci ence B.V.